Current installed costs of most solar heating systems are quite high, often in the range of twenty to thirty-five dollars per square foot. The solar collector is typically the most sophisticated part of such systems and requires great care and skill in fabrication and installation to insure efficient operation. Often the materials and techniques used to construct solar collectors are quite expensive and construction is best carried out at a special fabrication site, rather than at the installation site. In addition, some solar collectors tend to be large and heavy, which makes them difficult to maneuver and install and causes them to suffer from significant thermal lag: the delay of the collector in reaching a particular temperature. There is a constant need for improving heat transfer between the collector and heat-carrying fluid and thermal insulation between the collector and the surrounding environment.